摘要 |
<p>A controller inclines a movable body (WST) with respect to an XY plane at an angle ± in a periodic direction of a grating (39Y 1 , 39Y 2 ), based on a measurement value of an interferometer which measures an angle of inclination of the movable body to the XY plane, and based on a measurement value of an encoder system (62A, 62C) and information of angle ± before and after the inclination, and computes an Abbe offset quantity of the grating surface with respect to a reference surface (e. g., an image plane of a projection optical system) which serves as a reference for position control of the movable body in the XY plane. Then, the controller drives the movable body along the XY plane, based on positional information of the movable body in the XY plane measured by the encoder system and a measurement error of the encoder system corresponding to an angle of inclination of the movable body to the XY plane due to the Abbe offset quantity of the grating surface.</p> |